%0 Journal Article
%A A. L. Teptin
%T A new condition for the sign-constancy of the Green function
%J Differencialʹnye uravneniâ
%D 1988
%P 1066-1069
%V 24
%N 6
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1988_24_6_a25/
%G ru
%F DE_1988_24_6_a25